'I could easily have been a serial killer'

Grayson Perry, dazzling in pink and violet flounces, with sprigs of stick-on gems around both eyes, feels a special affinity with the artists in the exhibition he helped select.

"I could easily have been a serial killer if I hadn't been an artist," he says chattily.

Sir Joseph Pilling, former director of the prison service and chair of the Koestler Trust for art in prisons, blinks, momentarily nonplussed as to the correct civil response.

The artists whose powerful, hilarious and scary work is currently filling two large galleries at the ICA are released for a few hours to their workshops and classes from their cells in some of the toughest prisons in the country. Others live in high security hospitals, young offenders institutions, and some sit in immigration centres, awaiting deportation.

The pieces include a homage to Perry's own Turner prize winning work, a large pot made in HMP Dovegate in Stafforshire. It is inscribed "Homage to Grayson Perry who through his love of pottery and tapestry inspired me to do a homage to my love of tapestry and pottery. Thank you to the South Bank Show too."

"I was quite chuffed at the media reach I have, actually," Perry says.

"You've got people here with no inhibition control," he adds. "That's not very good if it's going to be mixed up in nefarious activities - but for artists it's a fantastic qualification."

"I think inevitably the temptation is to look at the pieces first and wonder what's their story, what's this guy in for - but that evaporates in a few minutes, and you're left with the quality of the work. Quite a few of these guys could easily make it in the art world outside."

The artists include a former professional cake maker, who each year submits an exquisitely detailed paper sculpture from Full Sutton in Yorkshire; a row of budgies drawn in loving detail by an artist in Broadmoor, titled My Birds, My Family, My Friends; and Day In Prison, from Wormwood Scrubs, a bar of soap carved into the words GET UP GET BORED GET FED GO TO SLEEP.

Inevitably, few of the artists were free to join Grayson Perry at yesterday's champagne launch at the ICA. But Rob came - he entered last year from Barlinnie in Glasgow, this year from probation, and won an "outstanding" commendation for both pieces. Art has played a major role in Rob's life, in surprising ways. Outside he was able to swap paintings for drugs with dealers - "generally they went for psychedelic stuff". Inside he had a flourishing trade, getting tobacco for portraits done from cherished photographs of wives, girlfriends and children. Now he is determined to stay clean, go to art college, and then university: his painting in the exhibition shows a man teetering on the edge of the gutter, the passersby looking at him with contempt.

"Generally we find we get some of the best stuff from the young offenders and from lifers," says Joss Blake, who helps run the Koestler awards. "The young ones are full of energy and ideas, and the lifers have a lot of time on their hands."